A considerable need exists in many technical areas for beams of low weight, high strength with regard to both resistance to bending and resistance to compression, and advantageous collapse characteristics. Such beams are desirable in the vehicle industry, the construction industry, the road equipment industry etc., and especially the passenger car industry, since an advantageous weight-to-strength ratio permits lower fuel consumption and advantageous collapse characteristics or a considerable capacity to absorb high energy in the course of deformation to a state in which the beam may be regarded as having collapsed. This latter characteristic is desirable in so-called impact protection zones in passenger cars, buses and lorries or similar vehicles.